SWAPPING STRUCTURAL DETERMINANTS OF RIBONUCLEASES - AN ENERGETIC ANALYSIS OF THE HINGE PEPTIDE-16-22

Citation
L. Mazzarella et al., SWAPPING STRUCTURAL DETERMINANTS OF RIBONUCLEASES - AN ENERGETIC ANALYSIS OF THE HINGE PEPTIDE-16-22, Proceedings of the National Academy of Sciences of the United Statesof America, 92(9), 1995, pp. 3799-3803
Citations number
24
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Multidisciplinary Sciences
ISSN journal
0027-8424
Volume
92
Issue
9
Year of publication
1995
Pages
3799 - 3803
Database
ISI
SICI code
0027-8424(1995)92:9<3799:SSDOR->2.0.ZU;2-R
Abstract
Bovine seminal ribonuclease (BS-RNase) is a homodimeric enzyme strictl y homologous to the pancreatic ribonuclease (RNase A), Native BS-RNase is an equilibrium mixture of two distinct dimers differing in the int erchange of the N-terminal segments and in their biological properties . The loop 16-22 plays a fundamental role on the relative stability of the two isomers. Both the primary and tertiary structures of the RNas e A differ substantially from those of the seminal ribonuclease in the loop region 16-22. To analyze the possible stable conformations of th is loop in both enzymes, structure predictions have been attempted, ac cording to a procedure described by Palmer and Scheraga [Palmer, K. A. and Scheraga, H. A. (1992) J. Comput, Chem, 13, 329-350], Results com pare well with experimental x-ray structures and clarify the structura l determinants that are responsible for the swapping of the N-terminal domains and for the peculiar properties of BS-RNase. Minimal modifica tions of RNase A sequence needed to form a stable swapped dimer are al so predicted.